MINERALS INDEX

Actinolite

Albite

Allactite

Allanite

Amphibole Group

Andradite

Anglesite

Anhydrite

Anorthite

Apatite

ApatiteGroup

Apophyllite

Aragonite

Arsenates

Arsenides

Arseniosiderite

Arsenopyrite

Aurichalcite

Axinite

Azurite

Barite

Barylite

Barysilite

Bementite

Biotite

Borates

Bornite

Boroarsenates

Bustamite

Cahnite

Calamine

Calcite

Calcium larsenite

Carbonates

Celestite

Cerusite

Chalcocite

Chalcophanite

Chalcopyrite

Chloanthite

Chlorite

Chlorophoenicite

Chondrodite

Chysolite Group

Clinohedrite

Copper

Corundum

Corundum Group

Crocidolite

Cummingtonite

Cuprite

Cuspidine

Cyprine

Datolite

Desaulesite

Descloizite

Diopside

Dolomite

Edenite

Epidote

EpidoteGroup

FeldsparGroup

Ferroaxinite

Ferroschallerite

Fluoborite

Fluorite

Franklinite

Friedelite

Friedelite Group

Gageite

Gahnite

Galena

Ganophyllite

Garnet

Glaucochroite

Goethite

Graphite

Greenockite

Gypsum

Halloysite

Haloids

Hancockite

Hardystonite

Hastingsite

Hedyphane

Hematite

Hetaerolite

Heulandite

Hodgkinsonite

Holdenite

Humite Group

Hyalophane

Hydrohetaerolite

Hydrozincite

Ilmenite

Jeffersonite

Kentrolite

Larsenite

Lead

Leucaugite

Leucophoenicite

Limonite

Lollingite

Loseyite

Magnesium- chlorophoenicite

Magnetite

Malachite

Manganbrucite

Manganite

Manganosite

Marcasite

Margarosanite

Mcgovernite

Mica Group

Microcline

Millerite

Molybdenite

Mooreite

Muscovite

Nasonite

Native Elements

Neotocite

Niccolite

Norbergite

Oxides

Pargasite

Pectolite

Phlogopite

Phosphates, Arsenates and Vanadates

Prehnite

Psilomelane

Pyrite

Pyrochroite

Pyroxene Group

Pyrrhotite

Quartz

Rhodochrosite

Rhodonite

Roeblingite

Roepperite

Rutile

Scapolite

Schallerite

Schefferite

Serpentine

Serpentine Group

Siderite

Silicates

Silver

Smithsonite

Sphalerite

Spinel

Spinel Group

Stilbite

Sulphates

Sulphides and Arsenides

Sussexite

Svabite

Talc

Tennantite

Tephroite

Thomsonite

Thorite

Titanite

Tourmaline

Tremolite and Actinolite

Unconfirmed Species

Vanadates

Vesuvianite

Willemite

Xonotlite

Zeolites

Zinc schefferite

Zincite

Zircon

Zoisite

 

Vesuvianite

Varieties beryllium vesuvianite and cyprine
Formula uncertain
Tetragonal

Forms
c(001), a(100), m(110), f(120), e(l01), p(111), t(331), and s(311)

Combinations on crystals of vesuvianite
  Forms Localities Illustration
1 c, a, m, p Penfield, Parker shaft  
2 a, m, r, e, p, t, s Canfield collection, Parker shaft  
3 a, m, p (beryllium vesuvianite) Franklin Figure 137

Occurrence
Although vesuvianite was named in all the older lists of Franklin minerals, its authentic discovery before 1899 is doubtful, green or brown tourmaline having been commonly mistaken for it. Small red crystals of simple form were noted by Penfield (179), embedded in nasonite from the, Parker shaft, and these he afterward verified by measurement (private communication to the author).

Figure 137
Prismatic crystal of vesuvianite showing the forms a(100), m(110), and p(111). Franklin.
fig137.gif (7845 bytes)

Similar but more complex crystals were seen in the same association in the Canfield collection.

A mineral from the Parker shaft, described by Chester (181) as granular vesuvianite, contains too much water properly to be assigned to that species.

Beryllium vesuvianite
In 1929 Mr. Bauer discovered the presence of beryllium in crystals of a complex silicate of unknown species shortly before discovered at Franklin. Crystallographic and optical tests established the mineral as vesuvianite, a determination with which the analysis was in agreement.

The new variety is found in slender brown prisms embedded in a coarsely granular mixture of green willemite, brown garnet, leucophoenicite, barite, minor amounts of svabite, gageite, and native copper.

The crystals show a simple combination of the unit pyramid, the prism of the first order, and the base, as shown in figure 137. They are of poor quality for measurement, as is so common with crystals of vesuvianite. Thirteen values of r for p(111) on four crystals gave an average value of 36 52', which gives the element c = po as 0.5303; Dana uses the value c = 0.5372.

The new variety is optically uniaxial and negative, with absorption in blue light w > e , and refractive indices w = 1.712, e = 1.700. The specific gravity is 3.385 0.002.

Cyprine
The fibrous copper-bearing variety cyprine was first observed by the author in 1905 in a small dump of unknown origin at the mouth of the Parker shaft. It was in bundles of slightly radiate needles scattered through a coarse-grained feldspathic pegmatite. It is abundant in the specimens and is conspicuous, as its color is blue to blue-green. With it are manganophyllite, yellowish garnet, and native copper in threads and irregular fragments.

As the mineral was not at first recognized as cyprine but was thought to be a new species, material for analysis was separated by crushing and handpicking and careful rejection of all traces of the associated metallic, copper, as the mineral itself contains copper in combination. Analysis 1 is similar to that of cyprine from Tellemarken, Norway, but differs from it in details.

In 1922 cyprine was found in abundance in the mine at Franklin, in a crosscut about 400 feet southwest of the Parker shaft and near the 850-foot level, and in the ore body but near the hanging wall. The cyprine was rather coarsely fibrous and was intimately intermingled with brown garnet, pale-pink bustamite, white willemite, and calcite. Part of it was of vivid sky-blue color, and part of it was bluish-green. Polished surfaces of the, blue cyprine presented a striking appearance. The refractive indices of the material of the several colors are as follows:

Refractive indices of cyprine
 

e

w

Blue-green cyprine, in pegmatite 1.696 1.710
Sky-blue cyprine, in ore 1.705 1.713
Green cyprine, in ore 1.712 1.719

The abundant cyprine found later at Franklin has been analyzed by Shannon (224) and by Bauer (225). The analysis by Bauer, no. 3, was made on material nearly one-third of which consisted of willemite, as seen in thin section, and which also contained minute specks of metallic copper. Mr. Bauer has also furnished the author with two previously unpublished analyses, nos. 4 and 5, of the green and blue portions, respectively, of a single specimen of the mineral, separated by hand picking. The specific gravity of the green portion was 3.45. The difference in color of the two portions does not seem to indicate much difference in composition.

Composition
Vesuvianite is a calcium aluminosilicate of complex and variable composition, for which no simple formula has yet been generally adopted. The chemical character of the Franklin vesuvianite is shown by the following analyses:

[Analyses of vesuvianite]

Analysis 6, made by Bauer (272) on a picked sample of the crystals found in 1929, shows the presence of more than 9 percent of beryllium oxide. The probability that beryllium would be found at Franklin in some form was foretold by the observation, by the German spectroscopist Eberhard (200) in 1912, of beryllium lines in the arc spectrum of Franklin willemite. As yet beryllium has not been detected in wet analyses of cyprine, though it may have been present and have been determined with the aluminum. Mr. Nitchie, formerly of the New Jersey Zinc Company's laboratory at Palmerton, Pa., found that cyprine shows spectroscopically strong lines of beryllium, although relatively less strong than in spectrograms of brown beryllium vesuvianite.

It now appears certain that the beryllium is not genetically associated with the primary willemite ore but is a post-ore element introduced into the deposit from intrusive pegmatite.

 


 
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